Cynodon

Cynodon is a genus of perennial herbaceous plant in the grass family (Poaceae). It has a dozen accepted species out of almost a hundred described ones.

Description

They are perennial, rhizomatous or stoloniferous plants that form lawns. The leafy stems are robust or slender with short internodes. The leaves are linear to filiform, flat, with a membranous or ciliated ligule. The inflorescence is fingered, sometimes with more than one whorl of spikes with the spikelets sitting unilaterally, imbricate, and laterally compressed. These spikelets have one —rarely two— flowers with subequal, narrow, herbaceous glumes, with a pointed apex and a single nerve (or three on the upper one); Are both persistent or only the lower one? The lemma is navicular and with a generally pubescent keel, with three veins and no edge, while the palea is biquilled. Its fruit (Caryopsis) is elliptical in shape and laterally compressed with the embryo reaching half its length.

Distribution and habitat

Almost all species are native to the tropics of the Old World, especially Africa, while one of them is pantropical and widespread in all warm and temperate regions of the world. Some species, most commonly Cynodon dactylon, grow as meadow grasses in temperate regions, where they are valued for their drought tolerance compared with other meadow grasses. In many cases it is considered a weed that is difficult to eradicate with herbicides or by mechanical control without damaging the rest of the vegetation due to the rhizomes and stolons that, even if they break, leave underground plant structures and then repropagate.^{[ citation required]}

Taxonomy

The genus was described by Louis Claude Marie Richard and published in Christiaan Hendrik Persoon Synopsis Plantarum, vol. 1, no. 159, p. 85[1], 1805. The type species is: Cynodon dactylon (L.) Pers.

Etymology

Cynodon: generic name derived from the Greek χυνο, dog, and όδού, tooth, perhaps in allusion to the hard, tapered, conical basal buds on the rhizomes.

Cytology

The basic chromosome number of the genus is x = 9 and 10, with somatic chromosome numbers of 2n = 16, 18, 27, 36, 40 and 54, since there are diploid species and a polyploid series. Relatively 'small' chromosomes. Persistent nucleoli.

Species

Includes the following species:

• Cynodon aethiopicus Clayton & J.R.Harlan
• Cynodon barberi Rang. & Tadul.
• Cynodon coursii A.Camus
• Cynodon dactylon (L.) Pers.
• Cynodon incompletus Nees
• Cynodon × magennisii Hurcombe
• Cynodon nlemfuensis Vanderyst
• Cynodon parviglumis Ohwi
• Cynodon plectostachyus (K.Schum.) Pilg.
• Cynodon radiatus Roth
• Cynodon transvaalensis Burtt Davy